ChangeLog

CPACSCreator Version 1.0.0
-------------
-/08/2018


    - General Changes:
       -

    - New API functions:
      - ``::tiglWingComponentSegmentPointGetEtaXsi`` computes the eta/xsi coordinates of a point on the component segment.
      - ``::tiglIntersectWithPlaneSegment`` computes the intersection of a CPACS shape (e.g. wing) with a plane of finite size.
      - ``::tiglGetCurveIntersection`` to compute the intersection of two curves.
      - ``::tiglGetCurveIntersectionPoint`` to query the intersection point(s) computed by ``::tiglGetCurveIntersection``.
      - ``::tiglGetCurveIntersectionCount`` returns the number of intersection points computed by ``::tiglGetCurveIntersection``.
      - ``::tiglGetCurveParameter`` projects a point onto a curve and returns the curve parameter of the point.
      - ``::tiglFuselageGetSectionCenter`` computes the center of a fuselage section defined by its eta coordinate.
      - ``::tiglFuselageGetCrossSectionArea`` computes the area of a fuselage section.
      - ``::tiglFuselageGetCenterLineLength`` computes the length of the centerline of the fuselage.
      - ``::tiglCheckPointInside`` checks, whether a point lies inside some object (defined by its uid).
      - ``::tiglExportFuselageBREPByUID`` and ``::tiglExportWingBREPByUID``

    - Changed API:
      - Removed deprectated intersection functions. These include
       - tiglComponentIntersectionLineCount
       - tiglComponentIntersectionPoint
       - tiglComponentIntersectionPoints

    - Fixes:
      - TiGL Viewer: Fixed missing fonts on macOS

    - Language bindings:
      - Python: the tiglwrapper.py module was renamed to tigl3wrapper.py. The Tigl object is renamed to Tigl3.
      - Java: the tigl package moved from de.dlr.sc.tigl to de.dlr.sc.tigl3

    - TiGL Viewer:
       - New design
       - Custom OpenGL shaders. If problems with the 3D rendering occur, please file a bug.
       - Display of reflection lines to inspect surface quality.
       - Display of textured surfaces.
       - Angle of perspective can be adjusted using the scripting API with ``setCameraPosition`` and ``setLookAtPosition``.
         This allows e.g. to create videos of the geometry.
       - Option to display face names.
       - Number of U and V iso-lines can be adjusted independently.




Version 3.0.0
-------------
-/01/2018

    - General Changes:
       - CPACS 3 compatibility, including the new component-segment coordinate-system math.
           - Note: As CPACS 3 is not officially released yet, the development version of CPACS as of December 18th, 2017 is used.
           - Note: The wing structure is not yet adapted to CPACS 3 but uses the 2.3 definition.
       - Guide curve support for wings and fuselages for high-fidelity surface modeling according to the CPACS 3 defintion.
       - Automated creation of CPACS reading and writing routines. This allows much
         better vality checks of the CPACS document.
       - Improved speed of ``::tiglFuselageGetPoint`` function. Also, the paramter xsi is now interpreted as the relative
         curve parameter instead of the relative circumference.
       - The TIGL library was renamed to tigl3. The TIGLViewer was renamed to tiglviewer-3.
       - The windows builds are now using the Visual C++ 2015 Toolchain.


    - New API functions:
      - ``::tiglWingComponentSegmentPointGetEtaXsi`` computes the eta/xsi coordinates of a point on the component segment.
      - ``::tiglIntersectWithPlaneSegment`` computes the intersection of a CPACS shape (e.g. wing) with a plane of finite size.
      - ``::tiglGetCurveIntersection`` to compute the intersection of two curves.
      - ``::tiglGetCurveIntersectionPoint`` to query the intersection point(s) computed by ``::tiglGetCurveIntersection``.
      - ``::tiglGetCurveIntersectionCount`` returns the number of intersection points computed by ``::tiglGetCurveIntersection``.
      - ``::tiglGetCurveParameter`` projects a point onto a curve and returns the curve parameter of the point.
      - ``::tiglFuselageGetSectionCenter`` computes the center of a fuselage section defined by its eta coordinate.
      - ``::tiglFuselageGetCrossSectionArea`` computes the area of a fuselage section.
      - ``::tiglFuselageGetCenterLineLength`` computes the length of the centerline of the fuselage.
      - ``::tiglCheckPointInside`` checks, whether a point lies inside some object (defined by its uid).
      - ``::tiglExportFuselageBREPByUID`` and ``::tiglExportWingBREPByUID``
	  - ``::tiglSetExportOptions`` sets exports-specific options
  
    - Changed API:
      - Removed deprectated intersection functions. These include
       - ``tiglComponentIntersectionLineCount``
       - ``tiglComponentIntersectionPoint``
       - ``tiglComponentIntersectionPoints``
      - Removed function ``tiglExportVTKSetOptions``. This is now replaced by ``::tiglSetExportOptions``

    - Fixes:
      - TiGL Viewer: Fixed missing fonts on macOS

    - Language bindings:
      - Python: the tiglwrapper.py module was renamed to tigl3wrapper.py. The Tigl object is renamed to Tigl3.
      - Java: the tigl package moved from de.dlr.sc.tigl to de.dlr.sc.tigl3

    - TiGL Viewer:
       - New design
       - Custom OpenGL shaders. If problems with the 3D rendering occur, please file a bug.
       - Display of reflection lines to inspect surface quality.
       - Display of textured surfaces.
       - Angle of perspective can be adjusted using the scripting API with ``setCameraPosition`` and ``setLookAtPosition``.
         This allows e.g. to create videos of the geometry.
       - Option to display face names.
       - Number of U and V iso-lines can be adjusted independently.


Version 2.2.1
--------------
18/08/2017

    - General changes:
        - Improved calculation time of ``::tiglFuselageGetPointAngle`` by roughly a factor of 30. The results might be a different than in previous versions, but the function should be more robust now.
        - Improved calculation time of ``::tiglFuselageGetPoint`` by applying caching. This leads only to a benefit in case of a large number of GetPoint calls (~30) per fuselage segment. This will be even improved in TiGL 3.

    - New API functions:
        - New API function ``tiglExportVTKSetOptions``. This function can be used e.g to disable
          normal vector writing in the VTK export.

    - Changed API:
        - Ignore Symmetry face in ``::tiglFuselageGetSurfaceArea`` for half fuselages
        - In ``::tiglFuselageGetPointAngle`` the cross section center is used as starting point of the angle rather than the origin of the yz-plane

    - Fixes:
        - Fixed bug, where the VTK export showed no geometry in ParaView
        - Improved accuracy of the VTK export. The digits of points are not truncated anymore to avoid duplicate points
        - Triangles with zero surface are excluded from the VTK export
        - Fixed incorrect face name ordering in WingComponentSegment

Version 2.2.0
--------------
23/12/2016

    - Major changes:
        - Added modelling of the wing structure, including ribs and spars . This code was part of a large
          pull request by Airbus D&S. Currently, the structure is only accessible by the TiGL Viewer.
          In future releases, we plan to make the structure accessible from the API.
        - Improved Collada export: The export is now conforming with the collada schema
          and can be displayed with OS X preview.
        - External shapes are added to the exports.
        - Added writing of modified CPACS files. Still, we do not offer yet API functions
          for modifications. Using the internal API, modifications are already possible.

    - New API functions:
        - New API function ``::tiglSaveCPACSConfiguration`` for writing the CPACS configuration into a file.

    - TiGLViewer:
        - Visualization of the wing structure.
        - Improved linking and compilation with Qt.
        - Added STL export of the whole aircraft configuration.


Version 2.1.7
--------------
22/09/2016

    - General changes:
        - Support for generic aircraft systems (by Jonas Jepsen).
        - External components are now conforming with the CPACS 2.3 standard (by Jonas Jepsen).
        - Support for rotorcraft (by Philipp Kunze).
        - Improved IGES export: Added support for long names in IGES (more than 8 characters as before).
        - Removed support for RedHat 5 and Ubuntu 13.10.
        - Added support for RedHat 7.
        - Ported to OpenCASCADE 6.9.0 and 7.0.0.

    - New API functions:
        - ``::tiglWingComponentSegmentComputeEtaIntersection``: This function should be used to compute points on the wing
           that lie on a straight line between two given points.
        - ``::tiglFuselageGetIndex`` to compute the index based on the fuselage UID.
        - Added new API functions for rotors and rotor blades:
          - ``::tiglGetRotorCount``
          - ``::tiglRotorGetUID``
          - ``::tiglRotorGetIndex``
          - ``::tiglRotorGetRadius``
          - ``::tiglRotorGetReferenceArea``
          - ``::tiglRotorGetTotalBladePlanformArea``
          - ``::tiglRotorGetSolidity``
          - ``::tiglRotorGetSurfaceArea``
          - ``::tiglRotorGetVolume``
          - ``::tiglRotorGetTipSpeed``
          - ``::tiglRotorGetRotorBladeCount``
          - ``::tiglRotorBladeGetWingIndex``
          - ``::tiglRotorBladeGetWingUID``
          - ``::tiglRotorBladeGetAzimuthAngle``
          - ``::tiglRotorBladeGetRadius``
          - ``::tiglRotorBladeGetPlanformArea``
          - ``::tiglRotorBladeGetSurfaceArea``
          - ``::tiglRotorBladeGetVolume``
          - ``::tiglRotorBladeGetTipSpeed``
          - ``::tiglRotorBladeGetLocalRadius``
          - ``::tiglRotorBladeGetLocalChord``
          - ``::tiglRotorBladeGetLocalTwistAngle``

    - Fixes:
        - Fixed parent-child transformations in case of multiple root components.
        - Fixed an error in ``::tiglWingComponentSegmentGetPoint`` in case of multiple intersections of the eta plane with the wing. 
          This was the case for e.g. box wings. (issue #176).
        - Fixed bug ``::tiglWingGetSpan`` in wing span computation when no wing symmetry is given (e.g. for a VTP) (issue #185 and #195).
        - Fixed another bug in ``::tiglWingGetSpan`` when the symmetry plane was the Y-Z plane (issue #174).
        - Fixed incorrect result in ``::tiglWingGetSegmentEtaXsi`` near wing sections, returning the wrong section (issue#187).
        - Fixed an issue in ``::tiglWingGetSegmentEtaXsi`` in case the airfoil is completely above the chord surface.
        - Fixed point projection on the geometry for large scale data (eg a factor of 1000) by making the convergence criterium size dependent (issue #203).

    - TiGLViewer:
        - Visualization of rotorcraft and rotorcraft specific menus.
        - Visualization of generic aircraft systems.
        - Added ``wingGetSpan`` function to TiGLViewer scripting.
        - Added script function ``wingComponentSegmentGetPoint``.
        - Fixed tiglviewer.sh script loading wrong OpenCASCADE libraries.

    - Language bindings:
        - Started experimental python bindings for the internal API.
          This allows a direct manipulation of the geometry objects
          from python together with the OpenCASCADE python bindings (pythoncc).
        - The source code of the matlab bindings is now shipped on all systems. In addition,
          we distribute a Makefile which can be used to compile the Matlab bindings when needed.
        - Added function ``::tiglWingComponentSegmentComputeEtaIntersection`` to java bindings.


Version 2.1.6
-------------
15/07/2015

    - TiGL Viewer:
        - Fixed critical crash on Windows 64 bit systems that occured sporadically on some systems


Version 2.1.5
-------------
01/07/2015

    - Changed API:
        - Added an output argument in the function ``::tiglWingComponentSegmentPointGetSegmentEtaXsi`` that returns the error of the computation.
        - The function ``::tiglWingComponentSegmentGetSegmentIntersection`` uses a new algorithm that should ensure straight 
          flap leading edges and straight spars. Also, a new parameter ``hasWarning`` was added, to inform the user, that the
          returned segment xsi value is not in the valid range [0,1]. This might be the case, if a spar is partially located outside the wing.
        - Removed macros TIGL_VERSION and TIGL_VERSION_MAJOR from tigl.h. Please use tigl_version.h instead.

    - General changes:
        - External geometries can be included into the CPACS file using a link to a STEP file. The allows e.g. the use
          of engines and nacelles. (Note: this is not yet included in the CPACS standard)
        - Improved computation of half model fuselage profiles. Now, fuselages are c2 continuous at the symmetry plane.
        - Improved computation speed of ``::tiglWingComponentSegmentGetPoint`` by a factor of 30 to 600 (depending on the geometry).
        - Reduced execution time of ``::tiglOpenCPACSConfiguration``.
        - All TiXI messages (errors/warnings) are now printed to the TiGL log.
        - Ported to OpenCASCADE 6.8.0.

    - New API functions:
        - ``::tiglExportFusedBREP`` to export the fused configuration to the BRep file format.

    - Fixes:
        - Fixed bug, where guide curves on half model fuselages were not touching the symmetry plane.
        - Fixed a TIGL_MATH_ERROR bug in ``::tiglWingComponentSegmentGetSegmentIntersection``.

    - TiGL Viewer:
        - Ported to Qt 5.
        - OpenGL accelerated rubber band selection. This fixes the slow rubber band selection on Linux and 
          the invisible rubber band selection on Mac.
        - Fixed bug when loading a CPACS file with multiple models (thanks Jonas!).
        - Removed support for legacy VRML and CSDFB files.


Version 2.1.4
-------------
06/02/2015

    - Changed API:
        - Added an output argument in the functions``tiglWingGetUpperPointAtDirection`` and ``tiglWingGetLowerPointAtDirection`` that returns the error of the computation

    - New API functions:
        -  ``tiglFuselageGetIndex`` and ``tiglFuselageGetSegmentIndex`` to retrieve the index of a fuselage and fuselage segment given a CPACS UID

    - Fixes:
        - Fixed some warnings using CMake 3

    - TiGL Viewer:
        - Fixed a crash in case of a missing model UID 
        - Fixed a bug, where debugging BREP files where always created on Linux
        - Improved scripting interface for wingGetLower/UpperPointAtDirection to return the error

    - Language bindings:
        - Completed the new Java bindings for TiGL 
        - Removed Fortran bindings since nobody is using them


Version 2.1.3
-------------
08/12/2014

    - Changed API:
        - Changed functions ``tiglWingGetSegmentSurfaceArea`` to exclude side faces and trailing edges
        - Removed functions ``tiglWingGetUpperPointAtAngle`` and ``tiglWingGetLowerPointAtAngle``. These functions
          were replaced by ``tiglWingGetUpperPointAtDirection`` and ``tiglWingGetLowerPointAtDirection``.

    - General changes:
        - Support for global transformation (translation refType="absGlobal"). Notice: some (incorrect) CPACS models will now look differently.
        - Accurate B-Spline approximation of CST curves using Chebychev approximation.
        - Implemented recursive fusing trimming for the use of e.g. bellyfairings. Added small cpacs example how to model a bellyfairing.
        - Implemented trimming of intersection curves with parent bodies and far fields
        - Improved computation of fuselage positionings. This should improve loading times of configurations 
          with large number of sections, since the algorithmic complexity is reduced.
        - IGES + STEP export: All wing faces are now classified as Top-Wing, Bottom-Wing, or Trailing-Edge.
        - IGES export: Changed units to mm.
        - IGES export: Implemented layers/levels .
        - The OCAF framework is no longer required to build TiGL.
        - The build system now uses the cmake config-style TiXI and OCE search mechanisms.

    - New API functions:
        - Added functions to get the B-Spline paramterization of fuselage and wing profiles:

            - ``tiglProfileGetBSplineCount``,  returns the of B-Splines a profile is built of.
            - ``tiglProfileGetBSplineDataSizes``, returns the size of the knot vector and the number of control points of one profile B-Spline.
            - ``tiglProfileGetBSplineData``, returns the knot vector and the control points.

        - Added functions ``tiglWingGetSectionCount`` and ``tiglFuselageGetSectionCount``
        - Added functions ``tiglWingGetSegmentUpperSurfaceAreaTrimmed`` and ``tiglWingGetSegmentLowerSurfaceAreaTrimmed`` to e.g.
          compute the surface area of a control device.
        - Added functions ``tiglWingGetChordPoint`` and ``tiglWingGetChordNormal`` to query points on the wing chord surface.
        - Added functions ``tiglWingGetUpperPointAtDirection`` and ``tiglWingGetLowerPointAtDirection``.

    - Fixes:
        - Fixed ``tiglWingComponentSegmentGetPoint`` in case of global wing transformations.
        - Fixed ``tiglWingComponentSegmentGetPoint`` bug, returning eta values > 1 (issue 107).
        - Fixed numerical inaccuracy of ``tiglWingGetPointDirection``
        - Fixed incorrect CST curves at for N2 < 1.
        - Fixed null pointer bug in IGES export.


    - TiGLViewer:
        - Highly improved scripting console:

            - Script file can be given as command line argument (using option --script)
            - Added function to export all objects to file
            - The main application objects can be scripted (i.e. app, app.viewer, app.scene)
            - Draw shapes, points and vectors from script
            - Make screenshots by command
            - Context menu for copy-paste actions
            - History with recent commands
            - Mouse support
            - More wrapped tigl functions
            - Improved stability
            - Exception handling
            - TiXI errors and warnings are printed on the console now

        - Added dialog to draw points and vectors.
        - Added dialog for screenshot settings, including option for white background.
        - JPEG and PNG support for background images.
        - Collada export for the complete configuration (i.e. support for multiple objects).
        - Cleanup of menu entries.
        - Fixed multiple opened CPACS documents in TiGLViewer.
        - Fixed 3D view flickering on Mac OS X with Qt 4.8.6.


    - Language bindings:
        - Added python 3 support of ``tiglwrapper.py``
        - Improved TiGL library loading error messages in python wrapper 
        - New Java bindings. Hand-written high level API not yet complete (not all TiGL functions wrapped).
          Low level API (autogenerated) can be used instead for unimplemented functions.
        - Added Java example (see share/doc/tigl/examples/JavaDemo.java)

    - Documentation:
        - Added chapter for TiGL Viewer and the TiGL Viewer scripting console.



Version 2.1.2
-------------
17/04/2014

    - Changed API:
        - The returned UID strings of the following functions must not be freed by the user anymore:

            - ``tiglWingGetOuterSectionAndElementIndex``
            - ``tiglWingGetInnerSectionAndElementUID``
            - ``tiglFuselageGetStartSectionAndElementUID``
            - ``tiglFuselageGetEndSectionAndElementUID``
            - ``tiglWingComponentSegmentPointGetSegmentEtaXsi``
            - ``tiglWingComponentSegmentFindSegment`` 
            
        - Changed behavior of ``tiglWingComponentSegmentFindSegment``. In case the specified point does not 
          lie within 1 cm of any segment, ``TIGL_NOT_FOUND`` is returned.
        - Changed behavior of ``tiglWingComponentSegmentPointGetSegmentEtaXsi``. If the specified point lies outside
          any segment so that the transformation can not be executed, ``TIGL_MATH_ERROR`` is returned.
        - The following API functions ``tiglComponentIntersectionPoint``, ``tiglComponentIntersectionPoints`` 
          and ``tiglComponentIntersectionLineCount`` are deprecated and will
          be removed in future releases. These functions are replaced by new intersection routines.
        - Removed functions ``tiglExportStructuredIGES`` and ``tiglExportStructuredSTEP``

    - General changes:
        - Completely reworked boolean operations with the following effects:

            - Fusing the whole plane is faster in many cases and more reliable
            - We keep track of the origins of each trimmed face which helps for
              the IGES and STEP exports
            - The boolean operations can be debugged now by setting the environment variable TIGL_DEBUG_BOP

        - Completely rewritten STEP and IGES exports:

            - Each face has now an identifier name
            - Inclusion of intersection curves
            - Inclusion of far fields into exports
            - IGES export in non-BREP mode since it is not supported by CATIA

        - Added new demos for C, Python and MATLAB. Please look into the documentation how to run them.
        - Added function for the intersection computation of a geometrical shape with a plane 
        - Experimental implementation of wing and fuselage guide curves
        - The mathematical orientation of wing profiles is checked for correctness
        - TiGL requires now at least OpenCASCADE 6.6.0 
        - Ported to OpenCASCADE 6.7.0

    - New API functions:
        - Added new API functions for shape/shape and shape/plane intersections:

            - ``tiglIntersectComponents``
            - ``tiglIntersectWithPlane``
            - ``tiglIntersectGetLineCount``
            - ``tiglIntersectGetPoint``

    - Fixes:
        - Fixed a bug in ``tiglWingComponentSegmentFindSegment``
        - Fixed numerical inaccuracy in the projection of points to a wing segment
        - Fixed crash in case of too long UIDs
        - Fixed some memory leaks 

    - TiGLViewer:
        - Improved IGES import: 

            - Multiple shapes are now imported as separate shapes from IGES files.
            - Fixed wrong scaling when importing IGES files.

        - Improved STEP export:

            - Files are now exported in units of meters instead of millimeters.

        - Improved BREP export and import: compound objects are now decomposed to separate objects.
        - Added method to export fused aircraft to BREP
        - Added method to export wing and fuselage profiles and guide curves to BREP
        - Fixed incorrect units in IGES and STEP export from save-as dialog.
        - General save-as dialog: All visible objects are saved to the file, if no shape is selected. 
          Otherwise, only the selected objects are exported.
        - Added debugging parameters to settings dialog. This includes:

            - Adapting number of displayed iso lines per face
            - Display face numbers
            - Debug boolean operations (if enabled, debugging shapes in BRep format are stored 
              to the current working directory)

        - Added new dialog for shape/shape and shape/plane intersections.
        - Added drag and drop support to TiGLViewer. Files (CPACS, IGES, STEP, BREP) are opened when they are dragged into TiGLViewer.
        - TiGLViewer displays far field after calculating the trimmed aircraft
        - Iso U/V lines are no longer displayed by default. This can be changed in the settings dialog.
        - The fused/trimmed aircraft geometry is displayed using a different color for each component.
        - Added visualization of wing and fuselage guide curves.
        - Fix: Only the first intersection curve was displayed. This is fixed now.
        - New icons


Version 2.1.1
-------------
Released: 28/01/2014

    - Changed API:
        - In previous TiGL version, some strings had to be freed manually after calling some functions. 
          These strings must not be freed anymore. Following functions are affected:

            - ``tiglWingGetOuterSectionAndElementIndex``
            - ``tiglWingGetInnerSectionAndElementUID``
            - ``tiglFuselageGetStartSectionAndElementUID``
            - ``tiglFuselageGetEndSectionAndElementUID``
            - ``tiglWingComponentSegmentPointGetSegmentEtaXsi`` 
            - ``tiglWingComponentSegmentFindSegment``

         - Changed return value of ``tiglWingComponentSegmentFindSegment``: In case the given point is 
           located more than 1 cm away from any segment, TIGL_NOT_FOUND is returned.
         - Changed return value of ``tiglWingComponentSegmentPointGetSegmentEtaXsi``: If the given point 
           lies outside any segment so that the transformation can not be executed, TIGL_MATH_ERROR is returned.


    - General changes:
        - Changed console logging to include errors and warnings by default
        - Wing profiles are automatically trimmed at their trailing edge to ensure, that the trailing edge is 
          always perpendicular to the chord line. This is required by the ``wingGetUpperPoint`` and ``wingGetLowerPoint`` functions.

    - Fixes:
        - Fixed a bug in ``tiglWingGetUpperPoint`` and ``tiglWingGetLowerPoint`` in which some points could not be calculated
        - Fixed two memory leaks


Version 2.1.0
-------------
Released: 17/01/2014

    - Changed API:
        - Added argument for ``tiglWingGetReferenceArea`` to define the projection plane for reference area calculations
    
    - General Changes:
        - Support for parametric CST wing profiles
        - Logging improvements. The console verbosity can now be set independent of file logging.
    
    - New API functions:
        - ``tiglWingGetMAC``, computes the mead aerodynamic chord length and position (thanks to Arda!)
    
    - Fixes:
        - Fixed crash in case of missing wing and fuselage profiles
        - Fixed accuracy errors in ``tiglWingSegmentPointGetComponentSegmentEtaXsi`` and ``tiglWingComponentSegmentPointGetSegmentEtaXsi``
        - Fixed a warning when including ``tigl.h``
        - Fixed numerical bug ``tiglWingComponentSegmentGetSegmentIntersection``
    
    - TiGLViewer:
        - Improved dialog for displaying wing component segment points
        - Added BRep export
        - Fixed crash on some Linux systems with strange LANG settings
        - Added dialog showing log history in case of an error


Version 2.0.7
-------------
Released: 21/11/2013

    - Changed API:
        - replaced ``tiglWingComponentSegmentGetMaterialUIDs`` with 
          ``tiglWingComponentSegmentGetMaterialUID`` and ``tiglWingComponentSegmentGetMaterialCount``
    
    - General Changes:
        - Implementation of far fields
        - More work on STEP and IGES export. The geometry is now exported as faces instead of solids in the STEP export.
        - Verification of airfoils during CPACS loading, this fixes twisted wing segments for some CPACS files
        - Improved modelling of leading and trailing edge
        - New Logging Framework
    
    - New API functions:
        - ``tiglWingGetSegmentEtaXsi``, to transform global x,y,z coordinates into wing segment coordinates
        - ``tiglExportFusedSTEP``, exports the trimmed/fused geometry as a step file
        - ``tiglWingComponentSegmentGetMaterialUID``, to get the material UID at a point of the component segment
        - ``tiglWingComponentSegmentGetMaterialThickness``, to get the material thickness at a point of the component segment
        - ``tiglWingComponentSegmentGetMaterialCount``, to get the number of materials defined at a point of the component segment
        - ``tiglLogSetFileEnding``, ``tiglLogSetTimeInFilenameEnabled``, ``tiglLogToFileDisabled``,
          ``tiglLogToFileEnabled``, ``tiglLogToFileStreamEnabled``, to modify logging settings
    
    - Fixes:
        - fixed a bug in ``tiglWingComponentSegmentGetSegmentIntersection``
    
    - TiGLViewer:
        - Loading of HOTSOSE mesh files
        - Auto-reload of non-CPACS files
        - Improved display of airfoils
        - Improved error dialogs


Version 2.0.6
-------------
Released: 27/08/2013


    - General Changes:
        - Improved loading times
        - Improved speed of intersection calculations by caching and reusing results
        - Switched to faces instead of solids in STEP Export 
        - Switched to const ``char * API``
        - Prepared TiGL for Android (currently working but still experimental)
    
    - New API functions:
        - ``tiglExportMeshedWingSTLByUID`` and ``tiglExportMeshedFuselageSTLByUID`` for STL export (Hello 3D printing!)
        - ``tiglWingComponentSegmentGetSegmentIntersection``
    
    - Fixes:
        - Fixed ``tiglFuselageGetPointAngle`` and ``tiglFuselageGetPointAngleTranslated`` giving wrong results (issues 89 and 92)
        - TiGL required positionings for all fuselage segments, this is now fixed (issue 57)
        - Fixed error when opening CPACS files with composite materials
        - Fixed wrong units in iges export (issue 78)
        - Silenced Error messages that weren't errors
        - Fixed different errors in ``tiglWingComponentSegmentPointGetSegmentEtaXsi``
        - Fixed duplicate log files
        
    
Version 2.0.5
-------------
Released: 11/06/2013

    - Changed API:
        - Switched to const ``char * strings``
        - ``tiglWingGetSegmentIndex`` returns now also the wing index instead of asking for it
        - Removed TiGL wire algorithms switching functions. Now a Bspline wire is used for each profile.
        
    - General Changes:
        - Symmetry modeling
        - Explicit modeling of the wing leading edge to improve tesselated output (no more leading edge bumps)
        - Explicit modeling of the wing upper and lower shape
        - The fuselage lofting now creates a smooth surface without hard edges (due to fixed OpenCASCADE bug)
        - Completely rewritten VTK export:

            - Full body export including wing segment metadata
            - Fixed lots of errors. 
            - Large improvement of calculation times. 
            - Provides wing segment metadata in a proper VTK-way, to allow visualization of these data in VTK viewers.
              Calculation and export of the proper normal vectors.
    
        - IGES and STEP export with CPACS metadata
        - Collada export for use in 3D rendering programs like Blender
        - MATLAB bindings for TiGL!
        - Completeley rewritten python bindings (e.g. better support for arrays)
        - Added logging framework to write outputs into log files (google-glog)
        - Ported to OpenCASCADE 6.6.0
        
    - New API functions:
        - ``tiglWingComponentSegmentGetMaterialUIDs``, to query materials on component segment
        - ``tiglWingComponentSegmentGetPoint``, to query cartesian point on the wing component segment (on chord surface)
        - ``tiglWingSegmentPointGetComponentSegmentEtaXsi``, to compute segment to component segment coordinates
        - ``tiglWingComponentSegmentGetSegmentUID``, queries the uids of the ith segment of the component segment
        - ``tiglWingComponentSegmentGetNumberOfSegments``, queries the number of segments belonging to a component segment
        - ``tiglExportFuselageColladaByUID``
        - ``tiglExportWingColladaByUID``
        - ``tiglExportStructuredIGES``
        - ``tiglExportStructuredSTEP``
        - ``tiglConfigurationGetLength``, returns the length of the airplane
        - ``tiglWingGetSpan``, returns the wing span
        - ``tiglComponentIntersectionPoints`` (convenience function, vectorizes ``tiglComponentIntersectionPoint`` to improve speed)
        - ``tiglExportMeshedGeometryVTKSimple`` and ``tiglExportMeshedGeometryVTKSimple`` (replaced dummy implementation)
        
    - Fixes:
        - Intersection calculation used by ``tiglComponentIntersectionPoint``
        - Fixed incorrectly placed fuselage positionings
        - Fixed ``tiglWingComponentSegmentFindSegment`` returning segments that don't belong to the component segment
        - Workaround to buggy OpenCASCADE boolean fuse algorithms (which seems to be non-commutative). As a result, the fusing of the whole plane
          can be slower than before.
        - Removed warning about missing component segments
        
    - TiGLViewer:
        - Display user defined component segment point
        - Improved speed of intersection calculation
        - Improved speed of shape triangulation
        - Display upper and lower shape of the wing
        - Display of the full model incorporating the symmetry properties of the CPACS components
        - Fixed detection, if CPACS file is changed while displayed in TiGLViewer
        - An optional control file can steer some basic settings like tesselation/triangulation accuracy (e.g. to tune speed of cpacs file opening)
        - STEP export
        - Settings Dialog (tesslation accuracy settings, background...)
        - New icon and color scheme


Version 2.0.4
-------------
Released: 17/01/2013

    - New API Functions: 
        - Added function ``tiglGetErrorString``

    - Fixes:
        - Fixed bug in ``tiglWingComponentSegmentPointGetSegmentEtaXsi``
        - Fixed camberline / chordline bug
        - Fixed exception, when no airfoils are available


    - TiGLViewer:
        - Added scripting interface to TIGLViewer. It is now possible to call TIGL/TIXI functions from within the TIGLViewer. The output is displayed in the console-view. Find more information here.
        - Added context-popup menu on right click. Available actions:
    
            - Removing of geometric shapes
            - Set transparency level of geometric shapes
            - Set color of selected shapes
            - Set material of selected shapes
            - Set wireframe/shading of selected shapes
    
        - Works now also in Mac OSX (since opencascade commit 4fe5661 )
        - Added toolbars
        - Added option to load a background image
        - Added autosave of user settings
        - Menus are disabled/enabled depending on dataset
        - Script could be loaded from file via File->open Script
        - Fixed opening from command line
        - Fixed bad font rendering for OpenCascade? > - 6.4.0


Version 2.0.3
-------------
Released: 17/01/2013

    - General Changes:
        - Added ``CCPACSWingSegment::GetChordPoint`` to internal API
        - Added a simple cpacs data set for accuracy testing
        - Added some accuracy tests for getPoint functions
        - Added support for visual leak detector
        - Changed UnitTesting? Framework to google-test
        - Changed TIGL linking to static for unit tests
        - Added coverage with gcov (gcc only) to project

    - New API Functions:
        - ``tiglWingGetIndex`` Returns the wing index given a wing UID
        - ``tiglWingGetSegmentIndex`` Returns the segment index given a wing segment UID
        - ``tiglWingGetComponentSegmentCount`` Returns the number of component segments for a specific wing (selected by wing index)
        - ``tiglWingGetComponentSegmentIndex`` Translates component segment UID into component segment index
        - ``tiglWingGetComponentSegmentUID`` Translates component segment index into component segment UID

    - Fixes:
        - Fixed ``tiglWingComponentSegmentPointGetSegmentEtaXsi``
        - Fixed accuracy of ``CCPACSWingComponentSegment::getPoint``
        - Fixed accuracy of ``CCPACSWingSegment::getEta``
        - Fixed memory management handling of ``tiglWingGetProfileName``
        - Fixed memory leaks in VTK export
        - Fixed memory leak in ``CCPACSFuselages``

    - TIGLViewer:
        - Menus are enabled/disabled depending on number of wings/fuselages
        - Added close configuration menu entry
        - improved view rotation with middle mouse button


Version 2.0.2
-------------
Released: 16/10/2012

    - General Changes:
        - Fixed wing translation bug in TIGLViewer and export Functions
        - Implemented STL import
        - The result of the fused plane calculation is now chached 
    
    - TiGLViewer:
        - Fixed triangulation algorithm (should not crash anymore)
        - Added full plane triangulation
        - Checks in all Selection-Dialogs, if cancel was pressed
        - Added calculation of intersection line of Wing and Fuselage
        - The recently opened folder is now saved
    

Version 2.0.1
-------------
Released: 02/10/2012

    - General Changes:
        - Fixed geometry transformations like sweep angle and dihedral angle rotating sections
        - Fixed scalings that lead to a translation of sections
        - Datasets with CPACS Version < 2.0 are now rejected
        - Calculation of fused fuselage, wing, and airplane should not crash anymore
        - Removed memory leaks
        - Cmake based project files
        - Prepared for OpenCascade? 6.5.3
        - Windows 64 Bit builds available
    
    - TiGLViewer:
        - Fixed inconsistent hot keys and menu entries for views
        - Console window showing outputs of TIGL and OpenCascade?
        - Wireframe mode
        - Recent Documents menu entry


Version 2.0
-----------

    - General Changes:
        - Compatible with CPACS 2.0
        - Corrected the implicit rotation of fuselage and wing profiles. They shouldn't turn from x-y to x-z by TIGL
        - TIGL now uses the coordinate system of parent components for child components. This is only done when parent --> child 
          relations could be figured out via UIDs.
        - Profile points could now also be stored as the vector (x ,y, and z) containing all profile points.
        - Some XPath have changed in CPACS 2.0, for example "sweepangle" is now "sweepAngle". TIGL is taking care of these changes.

    - New API Functions:
        - ``tiglFuselageGetSymmetry`` and ``tiglWingGetSymmetry`` for querying symmetry information
        - ``tiglWingGetReferenceArea`` gives the reference area of a wing
        - ``tiglWingComponentSegmentFindSegment`` returns the segmentUID and wingUID for a given point on a componentSegment
        - ``tiglWingGetWettedArea`` a new function for caluclating wetted area of a wing
        - ``tiglWingComponentSegmentPointGetSegmentEtaXsireturns`` eta, xsi, segmentUID and wingUID for a given eta and xsi on 
              a componentSegment
    
    - TiGLViewer:
        - Complete rebuild of TIGLViewer. It is now QT based and platform independent
        - TIGLViewer now updates the view when the cpacs file is changed.


Version 1.0
-----------
Released: 31/08/2011

    - Changed API:
        - ``tiglOpenCpacsConfiguration`` now opens a configuration without specification if the uid if it is the only one 
          in the data set. Simply take NULL or en empty string as uid argument.
        - Added a Python wrapper for the C-code and DLL handling (no need to manually convert cpython variables to python)

    - New API Functions
        - ``tiglComponentIntersectionPoint`` Returns a point on the intersection line of two geometric components. Often 
          there are more one intersection line, therefore you need to specify the line.
        - ``tiglComponentIntersectionLineCount`` Returns the number if intersection lines of two geometric components.
        - ``tiglComponentGetHashCode`` Computes a hash value to represent a specific shape. The value 
          is computed from the value of the underlying shape reference and the Orientation is not taken into account.
        - ``tiglFuselageGetMinumumDistanceToGround`` Returns the point where the distance between the selected fuselage 
          and the ground is at minimum. Fuselage could be turned with a given angle at at given axis, specified by a 
          point and a direction.

    - TIGLViewer
        - now could draw the componentSegment of a selected wing.


Version 0.9
-----------
Released: 29/04/2011

    - General Changes:
        - Fixed a bug that leads to strange errors when the first positioning of a Wing is not in the origin and has not 
          innerSectionUID-element.
        - Removed annoying strErr message when a point miss one parameter.
        - TIGL 64-Bit libs are available for linux.
        - TIGL is now able to open rotocraft configurations as well as aircraft